Hammer mill-type comminutating or pulverizing apparatus has heretofore been developed and utilized in effecting a size reduction of many types of solid waste materials with attempts at achieving a design for both improved waste disposal and for facilitating reclamination of materials of substantial economic value and capable of being remanufactured. Examples of such materials and operations include the shreading and tearing of large metal objects such as automobile bodies which contain metallic materials that have substantial economic value for remanufacture is reducable to more readily transportable configurations and useable particle size. Other materials subjected to comminutating action of hammer mills include solid waste that may include wood, stone, concrete and brick materials wherein it is advantageous to reduce the sizes of such materials to facilitate their transport to suitable waste disposal sites or further disposal operations. The solid wastes which often include friable materials such as stone and concrete, are best reduced by an impact type action of a pulverizer hammer. However, non-friable materials, such as waste paper and automobile bodies, are more easily reduced by a slicing or shearing action rather than by the blunt force produced by the conventional impact type pulverizer hammers.
Pulverizer apparatus heretofore utilized for such operation generally incorporates hammers that are generally configured as elongated steel bars of rectangular cross-section having a specific width and an edge or surface which forcibly impacts the materials during revolution thereof in a suitable housing provided with breaker bars. A number of these hammers are conventionally mounted on supporting rotor plates and revolved at a relatively high velocity to produce the impacting forces required for pulverization or comminutation of materials of the illustrative types. These rectangular cross-section hammers heretofore employed in such apparatus, in general, only have an impacting edge surface, or leading transverse end edge, which is effective in only providing an impact or tearing type of action with respect to the materials introduced into the pulverizer. These hammers operate in conjunction with a set of transversely disposed breaker bars against which the tearing action is achieved and an impacting force can be applied as a consequence of the logding of a particle of waste material against a breaker bar of the pulverizer housing. This lodging of the particles enables the hammers to be revolved into contacting engagement with the particle or particles to develop an impacting force for the further pulverization thereof.